Yaesu: System Fusion distance measurements

[k6cpo]

The question of how System Fusion measures the distance between radios came up during an informal net this morning. The participants were communicating between stations in the Imperial Valley (CA), Yuma, AZ and San Diego through a Fusion repeater located on Mt. Laguna, east of San Diego. Some of the distances shown on the radios seemed to be fairly accurate, while others seemed way off. Everybody was curious if the distance was between stations directly or if the distance from the station to the repeater entered into the calculation.

After the net, I did a distance measurement in Google Maps between my location and the NCO' location. It was within 0.2 mile of what showed on my radio, but we are almost directly in line with the repeater.

Can anyone enlighten me on how this is measured?

 

[OhSixTJ]

I know with d-star it uses the radios built-in GPS. Maybe yaesu does the same.

 

[willstuder]

System Fusion radios use their internal GPS or in some cases like the ft-991, manually entered GPS coordinates. All such radios can alternately have the coordinates entered manually. The repeaters however, do not have GPS coordinates. They just add up the distance between the two GPS units. You can use them with or without a repeater and get the same data. The repeater is just passing it along.

 

[k6cpo]

I found the answer to my question after doing some testing. I contacted a fellow club member and we tried DN simplex and DN through two different repeaters. The mileage shown on our radios was the same for all three conversations and was within a tenth of a mile of the distance shown on Google Maps between our stations (10.3 miles). One repeater was 3.5 miles from him and 8.9 from me and we're both about 45 miles from the other repeater.